Go try it now. Connect your laptop to your tv, set the refresh rate to 30hz. Your mouse will become extremely "laggy" (e.g. unresponsive), all 60fps animations like dragging windows around, scrolling will become stuttered, etc.
Just the productivity decrease alone makes this monitor extremely expensive in the end, despite its price.
No need for a TV set, some (most?) computer monitors can display 30 Hz, it only needs to be enabled using "custom resolution" or similar setting in drivers.
I just tried:
- Dragging windows - not an issue, but maybe I am used to it from times when having window contents displayed during dragging lagged much more due to cpu/gpu power.
- Scrolling - it is slower, but with clickless scroll wheel and smooth scrolling it was not too noticeable.
But, oh god, the mouse cursor movement... It was like working through a high latency VNC.
Just the productivity decrease alone makes this monitor extremely expensive in the end, despite its price.